Date Calculator

How to use this calculator

Enter your values after choosing the type of calculation in the tabs. The result updates as you type; press Calculate to confirm and jump to the result on mobile. Use Share to send the calculator with your result.

How date math works here

Years and months are applied first on the calendar (keeping the day of the month, or using the month’s last day if it doesn’t exist), then weeks and days are added as exact days. So January 31 + 1 month = February 28 (or 29), then + 1 day = March 1.

For simple “N days from today” questions, the Days From Today Calculator is quicker.

Frequently asked questions

About this tool

Written by

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Reviewed by

Formula tests passed · human review pending

Last updated

31 Oct 2026

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